Trench searchlight



E. A. SPERRY.

TRENCH SEARCHLIGHTY. APPLICATION FILED APR. 3, 19.17.

1.403,87@ Patented Jan. 17, 1922 3 SHIzETS-SHEET lif l IATTORNEY E. A.'SPERRY.

msnen szARcmlsHr.

- l APPLICATION FILED APR. 3,1917. l,-1(')3,8'76, Patented Jn. 17, 1922.

3 SHEETS-SHEET 2.

INVENTOR ELMER A. SPERRY l BY I Myx/.5%

ATTORNE E. A, SPERRY.

TRENCH SEARCHLIGHT.

APPLucAVTloN HLED APR.3-,1917.

1;403,876 v PatentedJan.17,1922,

SSHtETSA-SHEET 3.

8l --lll 84 [LME/Q. A. SPE/@HY UNITED STATES PATENT OFFICE.A

ELMER A. SPERRY, OF BROOKLYN, NEW YORK.

TRENCH sEARCHLIGHT.

appiietionnied April a, i917.

' New York,lhave invented certain new and cation. This invention relatesto searchlights -for showing the searehlight in a different tionaffording even greater security.

usefulI Improvements in Trench Searchlights,- of which the following isa specifiuse 'on battle fields, either tov illuminate thefieldlitselfnor the sky above it.

The object of the invention is to devise a searchlight'of'the typedisclosed in my copending application, Serial No. 99,715, filed May1916, whichmay be operatedfrom a position immune or substantially immunefrom enemy gunfire, andl which may, when necessary, be operated at highangles for detecting air craft or for other purposes, without subjectingthe projector to in]ury by hot particles which occasionally fall fromthe arc. Y

Referring. to the drawings in whichA what'v I now`consider to be thepreferred forms of my invention Aare shown Fig.v 1 is an elevation ofa.l searchlighti constructed according my invention. Fig. 2 is asideelevation of mechanism for controlling a pan' for catching hot particlesi falling from the arc.

F ig.V 3 is a diagrammatic view mechanism.

Fig. f1 is a detail ofthe mechanism.

of said Fig. 5 is a detailed view of a cup forl-k catching hot materialfalling from the negative carbon.

Fig. 6 is a section taken` on line 6-6, Fig. l showing the means forturning the searchlight.

Fig. 7 is a modification of the invention posi- F ig;Y 8 is a detailshowing a universal joint used on one of the mirrors.

iFig.` 9 is a viewof the 'form of reflector i vwhich may be used in my'device.

Fig. 10 is a similar view of amo'dified form of reflector. Q Fig. 11 isa detail plan view of one form of shield which is employed forprotecting the searchlight.

Fig. 12 is a detail view of one forni of catch pan.` l

According to my invention, I design the Specification of Letters Patent.

the like. The searchlight in a normally vertical position, so that the.

' the searchlight,

' portion of. the drum "side, of the pivot to provide a chain or cord 92Patented Jan. 17, 1922. serial No. 159,396.

searchlight 1 so that it ma)y be operated from a position entirely belowthe ground in a sheltered pit 2 or behind a parapet or may be mountedbeam is projected vertically. Positioned above the lamp on a post ormast 3 is a re Hector or mirror 4, preferably inclined at an angle to.theA vertical, so that the reflectedbeam will be approximatelyhorizontal. The mastis preferably made of a plurality-of sections 5and'6 so that it may readily be dismantled.

The 4mirroni may` be of-gthe usual material and if -desired may be made'in sec' tions as-shown in Fig. 9,.so that the breaking of one of thesections 115 need not affect thel others. Or it may be made of polishedmetal, so as not to be damaged to any great extent by small bullets andfragments of shells. .'Freferably I use a mirror 115 of glass reinforcedby wire netting as shown in F ig.' 10, as the glassmay be shatteredconsiderably and still`serve reasonably well. In order to prevent brokenpieces of the mirror from falling upon the glass front of I may providea wire netting screen 116 stretched across a hoop 7 beneathV themirrorf'as shown in Fig. 11. Hanging from hoop 7 is also provided anopaque screen 8 to conceal the beam rising from the searchlight, andthus render it- `more diiiicult'to locate the source of the light.

rI he mirror 4 is' shown fastened to membei' 9/itting slidably overvmast 3 and guide strip 10 thereon, and may be raised or low-l ered bymeans ofcable 11. Hoop 7fastened to member 12 slidably fitting over themirror 4 may be controlled by revolving or tilting the searchlight drum,while the mirror and mastbeing secured to the drum by brackets 17 and 18will continue to bear the.

rum is pivot# same relation thereto. The d ally supported at 117 by legs111 on'the revolving portion of the base 28; the major being on theopposite the mast so that each may counterbalance the other. I may alsoon mirror 4, so

that the mirror may be 'tilted separately on Y pivot 118 if desired,forslight changes in elevation of the beam.

The drum may be revolved by turning hand wheels 19 or 20 (Figs. 1 'and6)4 on shaft 21, on which is also mounted a beveled gear 22 meshing withanother beveled gear 23 on shaft 24. lShaft 24 which has its bearing inthe stationary part 25 of the base carries a pinion 26 meshing with aninternal, annular gearing 27 on the revolvable part 28 of the base uponwhich is mounted the drum. The drum may be tilted by turning wheels 29or-3O on shaft 31, on which is a bevel gear 32 meshing with anotherbevel gear 33 on shaft 34. Said shaftl is pro.

vided with a worm 35 meshing .with Vworm wheel 36 on shaft 37 providedwith pinlon V38. Pinion 38 through gear 39 on shaft 40 turns sprocketgear 41. Thedrum 1 is provided with a sprocket chain 42, over guide 43,meshing with sprocket gear 41. Any

movement of the drum carries with vit the mats and mirror.

For indicating the number ofdegrees through which the drum is turned, Imay provide scalesA 120 and 121.

vWhen using the light for anti-air-craft purposes, if the aircraft islow or distant the mirror 4 may be used, but when the air-` craft ishigh or overhead the mirror may be swung out of the path of the beam andthe light pointed Ydirectly at the object. To

swing the mirror out of the path of the beam, I may prov1de, fastened toanduextending part way 'around the mast, gearing 14, meshing with aworin 15 which may be turnedby the turning of rwheel 16.` This willcause i the mast to revolve in'its brackets 17 and 18.

- of course, under the arc..

Vhen the searchlight is pointing upwardly, the reflector within the drumis,

It therefore becomes necessary to protect this reflector from hotparticles which occasionally fall from the arc and .fuse into thepolished surface of the reflector. For this` purpose I prefer to employashield or pan 44 which may be pivotally supported so as toA hangvertically under the-arc. The pan may be made of mica orl similartransparent material. APreferably itis made of openwork metal, such v-asne .wire gauzeYV or screen as shown ,in

Fig. 12, Aso-that a minimum amount of light may be shut off thereby. Themesh of the 'screen should besuch as will check the passage of thesmallest particles that are capable of causing damage. The diameter ofthe wire usedinlthe screen should be sui- -cient'to conduct heat awayfrom a very hot particle fast lenough to prevent the wire itself fromfusing and allowing the particle to fall through upon the reflector.

I prefer toprovide automatic controlling means whereby the pan may bewithdrawn from the zone of light `when the drum is horizontal ornearlyhorizontal, andv for reare wound up by motor 52 and held in thisposition by pawl 53 and ratchet 54. A rod 55 on the outside of thesearchlight drum is connected at one end to the pawl for tripping thelatter. tionary'part 56 of the frame in which the searchlight ispivoted, is a cam 57 stationed in the path of rod 55. lVhen the light istilted to about 30 above the horizontal, rod 55 engages cam 57 and isthereby raised, tripping pawl 53 and releasing ratchet 54 so that thepan becomes free to fall into place below the arc.

I desire also to provide means for letting the pan Ydown gentlyggratherthan allow it to fall.. For this'purpose I mayemploy a retarding device"58 (Figs. 2 and F4). A ratchet wheel-'59 is rigidlyl mounted on shaft 51while gearGOisloosely'mounted thereon. It will be 'seen' that haft will4be free to turn in one: directie withoutjturning the whole trainvolf/gears m58, -whi-le-in order to turn in the other dire'ftib'it mistturn the wh'ole train of gearsincluding the star wheel 6-1 which mustalternately engage and dis-. engage points 62 and 63v rigidlyattached towheel 164; said wheel being pivoted at x64 and carrying a weight 65. Theinstrument -is so attached to shaft 51.asino,rta-rdyithe tlously, and toswingifr'e'ely so as to'always be directly under the'arc.- vI'n'thisposition a contact -66, one'`p'o,ii 1ft` 122`of` which `is located onlthe drum, aindth'e other pointA 123 on the rod 55 remains open.-y Butwhen the light is returned towardtheV horizontal far enough to allow rod55 to slipvofflfrom cam 57, contact 66 becomes closed.` Contact 67stationed in? the top of the drum is always closed when the pan is down,so that now a circuit is completed through motor 52, and the pan isdrawn up to the top of the searchlight drum, out -of the zone of light.lVhen it reaches this position it strikes and opens contact 67 and thewinding up mechanism stops working. The pan is held up and againstcontact 67 by pawl and ratchet 53 and 54, until rod 55 is again pressedoutwardly.

While the pan serves to catch all harmful Attached to kthe t sta.

particles falling from the arc, when itis constructed of metal gauze itis unable to Y catch the drippings of molten copper from may be overcomeby placing a small cup close to the source of these drippings. Such anarrangement is shown in Fig. The

cup is preferably made of a solid metal disc.

bottom 68 with sides 69 of fine metal gauze. A hole is provided in thebottom of thecup, to fit over the electrode 70. On the bottom `of' thecup are one or more ho'o'ks'71, to

ft over one or more small pins 72 in the carbon holder 73. When thelight is in a vertical or nearly vertical osition, the

l molten copper will fall intote bottom of the cup, but when the lightisata lower angle, the drippingswill fall against. the

sides. of the cup. Not having fallen ver)7 far, these drippings do notbreak up and splash around, Abut trickle down' the sides into'thebottom, of the cup. i

' The cup may be made of copper, in which case I prefer to plate it witha nonsoxidizing metal, such as nickel or'silver.

The s earchlight as shown in Fig. 1 is designed so thatit may also 'beused as a truck light, that is, it may be mounted and perated on amilitary truck or train. When so used, the mast and mirror 4 may beremoved and the light pointed directly at the object horizontallyor'vertically. Preferably, however, the mast andmirror are used 'evenwhen the light is used as a truck searchlight. Ordinarily atrucksearchlight on base 84.

is mounted on a mast so as to raise the source of light to anadvantageous height. Byplacingthe mirror above the truck, I amable toplace the light, which is very heavy, on thetruck, and obtain. alltheailvantages of an elevated source of light, andatV the same time,overcome the disadvantage of raising the entire searchlight to thedesired height.

As O ne ofthe objects of the invention is to provide asearchlight foruse in trench war-- fare, which will be safe from enemy gunfire, I haveshown-in Fig. 7 a modification, 1n which the searchlight'SO may be'placed entirely under round away from the rain of shrapnel, and stillbe capable of projectin a beam irectly in the path of the beam I rovidea reflector 8l pivoted by a universal joint 82 to post 83 which isrigidly mounted on a base 84. Above 'the surface 85 ofthe ground I pro`vide a second reiector 86 pivotally suppprted on arm 87 extending frommast 88.

ast Y88 is pivotally vfastened to bracket 89 at 90. Bracket `89 ispivotally fastenedto post 83 and provided with rollers 91 restingBy-turning bracket 89 and mast 88 around vtilting the mirror to, say thedotted line position. 93, the mast may be leaned backwardly as shown inthe dotted line position 94 fo;1 higher elevations of the beam.

For leaning the mast backward I may provide a segmental gear 95 securedto thel bottom ofthe mast, and meshing with pinion 96 on. bracket 89 andoperated by hand wheel 97. I

When -leaning the mast backward it becomes necessary to tilt'reilector81 as shown by vthe dotted line position 99 so that the beam maystillstrike mirror `86. This adjust'ment may be made manually, but ispreferably effected lautomatically by means of levers 101,'rigidlyfastened to mast 88 and 'pivotallv secured to bracket 89 at 102. Theseveral links of'levers 101 are pivotally secured to each other at 103',104, and 105. Members 106 and 107 of said levers are adapted to engagearing 108 rigidly suspended frominirror 81. It will readily be seen thatwhen the mast is tilted backward,-

mirror 81 will follow, thus keepinf the beam projected against mirror86. Vheu the mast 1s swung around -post 83 it will carry levers 101also, so' that the leaning of the mast from any position around mirror81 will` automat cally effect the necessary change of said mirror.

volving in azimuth through universal joint 82, I prefer to constructsaid joint as shown inF ig. 8 in` which 112 is a ball attachedto themirror. This ball is pivotally secured to gimbal ring 113, which is inturn pivot-` ally secured to the forked members 114 on the post 83. y I

In accordance with the provisions of the patent statutes, I have 'hereindescribed the .ments in thecornbination and relations described, some ofthese may be altereda'nd principle of operation of my invention,'toothers4 omitted without interfering with the moregeneral resultsoutlined, and the injector, means suppprting said'sl e 2. In asearchlightr'including a projector and a. source of` light, a projectorshield lo-A cated between said light source and said prold forpivotal`movement an axisj distance fronithe shield,v means ...for .moving saidsearchlight in elevation, means. con-l l. .trolledby the positionjjotthe searchlight -jffor'remo'ving saidshield `from its operative 25 lposition. y y

3, In a searchlight including-"a,y projector andya.` source oflight, aprojectomshield withinsaid searchlight, means for raising saidv shield-to inoperative position, means for moving said searchlight inelevation, and means responsive tol a predetermined i elevation of thesearchli ht for .releasing said shield from its raise position.

4. In a searchlight including Fa projector and a source of light, aprojector shield located between said light source and said projector,means for moving isaid searchlight in elevation, and means responsive.to

. the lowering of the searchlight to a predetermined position forremoving said shield from the zone of light. i

'5f Ina-searchlight including a projector and asource of light, aprojector shield lo cated betweenV the .projector and the light source,means for raising vsaid shield to a point without the light beam, meansfor the searchlight, and means controlled by the movement of thesearchlight for releasing said shield from. its raised position.

6. In a searclilight including a 'projector4 l' and a source of light,a. projector shield lo= cated between said projector and said source i yof light, means for moving the searchlight, means responsive to acertain position of the vsearchlight :tor removing said shield from saidlocation to'a location without the light beam and means for holding saidshield in an inoperative position.l 7. A military searchlight comprisinga drum supported on a horizontal axis in a vertical position, areiector, an adjustable means for :supporting said reflector aloft andmeans for concealing the light beam between said drum and saidreilector.

8. The combination with a normally vertical searchlight, of a mastmounted adja?. Y cent said light, a reflector supported onsaid mastandmeans for revolving saidamast` to turn said reflector without the beamot light.

9. A-jsearchlighft,f including a .drum rota.- tablefaboutgan axis and abase therefor, means fongtilting said drum about said axiscomp-risinga.plurality of gears located .on

.said base," a sprocket 'chain located on said drum engaging one of saidgears and means for turning said gears.

10. A searchlight, including a drum 4rotatable about an axis and a basetherefor,

Ameans'for tilting said drum about said axis comprising a plurality Aofgears located on said base, a vsprocket chain located-on said drumengaging one ,of said gears, means for turningsaid gears,'and means forturning said -dru'm in azimuth.

ll. In combination, a searchlight, a catch-r pan therefor movable bygravity to a pre-1 determined position, means for holding said catch-panin inoperative position, `means controlled by the position of thesearchlight for releasing the catch-pan to the action of gravity, andmeans for retarding the movement of said catch-pan to said predeterminedposition..

j l2. In combination, a searchlight adapted to be directed upwardly, areflector, means 'including a mast for supporting said relector` abovesaid searchliglit, means supported onsad mastfor concealingthe beam ofsaid light-v between said searchlight and reiector and means for raisingand lowering saidV last namedmeans.`

In testimony whereof I have affixed my signature. i I

ELilER A. ernaar;

